Mercedes-Benz S-Class Oxygen Sensor Replacement Parts

Oxygen sensors are fitted to petrol-engined S-Class models across all generations, where they monitor exhaust gases to help the engine management system control fuelling. Diesel S-Class variants (such as those badged S 320 CDI, S 350 d, or S 400 d) do not use a conventional lambda oxygen sensor in the same way, as diesel combustion works differently — if you have a diesel, you are more likely looking for a NOx sensor or a differential pressure sensor. Always check your engine code and fuel type before ordering, as the parts are not interchangeable across the two fuel types.

The W220 (1998–2005) and W221 (2005–2013) are distinct generations with different engine families, exhaust systems, and engine management strategies, so sensors from one generation will very rarely cross to the other. Even where a connector looks physically similar, the calibration and output signal may differ enough to cause fault codes or poor running. Name the generation to your breaker and confirm your engine code — for example M113, M272, or M278 — so they can pull the correct sensor from the right donor car.

Yes, engine code matters significantly here: the S 350 and S 500 use different engines (for example the M272 V6 versus the M273 V8 in the W221 era), which have different exhaust configurations, different numbers of sensors, and different sensor positions. A sensor from the wrong engine family on the same car in the same year is very unlikely to be a direct fit. Always match by engine code, not just by model year or displacement badge.

The W222 ran from 2013 to 2020, with a facelift in 2017 that brought updated engine variants and in some cases revised emission calibrations. For many petrol engines the sensor itself may be the same part across the facelift, but the 2017 update coincided with Euro 6 compliance changes on some models, which can affect sensor specification. Confirm your exact engine code with the breaker — not just the model year — to be certain the sensor from their donor car matches your emission era.

No, trim level does not affect oxygen sensor fitment on the S-Class — SE, AMG Line, and any other trim designation refer to cosmetic and equipment differences, not to the engine or exhaust system. What matters is the engine code and fuel type, which remain the same regardless of trim. You may find minor cosmetic differences on the exhaust tips or undertray panels on AMG-badged cars, but the sensor itself is determined by the engine, not the badge.

This is a question where you need to confirm specifics directly with your breaker against your exact registration, as catalytic converter and sensor compatibility across different emission eras is complex and strongly influences MOT outcomes. What is clear is that mixing components from different emission eras — particularly across the Euro 5 to Euro 6 boundary — risks sensor signals being misread by the ECU or the vehicle failing emissions tests. Give the breaker your full registration and engine code and ask them to confirm both parts came from a compatible donor vehicle.